This game presents in the figure below a black octahedron in perspective in a cartesian referential and a symmetry element either a tetrad rotation axis or a triad axis or a binary axis or a mirror plane or the inversion center in red  and one of the eight Miller indices of the octahedron faces in red parenthesis. The game comes to end after a click on all the Miller indices (at least one  and maximum of three) defining planes obtained by the operation of the given symmetry element on the plane with the Miller indices in red parenthesis.
Each correct choice is scored by a funny face and bad choice with a bad face. Finally the starting time and end time is given.

Theme table
 

Presentation